Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

2002

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 2641 - 2670 of 3128

Full-Text Articles in Physical Sciences and Mathematics

Hat Derivatives, Stephen B. Maurer , '67 Jan 2002

Hat Derivatives, Stephen B. Maurer , '67

Mathematics & Statistics Faculty Works

No abstract provided.

Go to article

Bouncing Branes, Emil Prodanov Jan 2002

Bouncing Branes, Emil Prodanov

Articles

Two classical scalar fields are minimally coupled to gravity in the Kachru-Shulz-Silverstein scenario with a rolling fifth radius. A Tolman wormhole solution is found for a R x S^3 brane with Lorentz metric and for a R x AdS_3 brane with positive definite metric.

Go to article

Characterization Of The Lower Atoka Formation, Arkoma Basin, Central Arkansas, Kelly R. Lagrange Jan 2002

Characterization Of The Lower Atoka Formation, Arkoma Basin, Central Arkansas, Kelly R. Lagrange

LSU Master's Theses

The Carboniferous Lower Atoka outcrops in the Arkoma Basin of Central Arkansas contain turbidite deposits in a channelized and unchannelized submarine fan setting. The objectives of the study were to determine depositional characteristics and reservoir performance of these fine-grained submarine fan deposits. Four outcrops (Highway 5, Perryville, Chula, and Danville) were studied and described in detail emphasizing sedimentary facies, vertical succession of beds, sedimentary structures, and other small-scaled features that cannot be resolved in subsurface deposits. Five distinct sedimentary facies were recognized: Facies A - massive sandstones, Facies B - thin-bedded sandstones with a mudstone drape, Facies C - interbedded …

Go to article

Water Discharge Models, Seasonal Effluent Mass Loading, And Best Management Practices For Crawfish Ponds, Landon David Parr Jan 2002

Water Discharge Models, Seasonal Effluent Mass Loading, And Best Management Practices For Crawfish Ponds, Landon David Parr

LSU Master's Theses

Nearly 35,000 ha are used to grow crawfish in southwest and south-central Louisiana, and many of these ponds discharge into impaired water bodies. In 2002, proposed guidelines were published by the United States Environmental Protection Agency (USEPA) assigning effluent limitations and standards for some aquaculture production systems and exempting others (e.g. crawfish ponds). This research had three objectives relative to crawfish ponds: develop water discharge models; final drawdown effluent quality and seasonal mass loading of solids and nutrients; and identification of Best Management Practices (BMPs) that could reduce effluent discharge and improve effluent quality. Models for south-central and southwest Louisiana …

Go to article

Sedimentology And Stratigraphy Of The Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera And Altiplano, Central Andes, Bolivia: Implications For The Tectonic Development Of The Central Andes, Richard John Fink Jan 2002

Sedimentology And Stratigraphy Of The Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera And Altiplano, Central Andes, Bolivia: Implications For The Tectonic Development Of The Central Andes, Richard John Fink

LSU Master's Theses

The Upper Cretaceous-Paleocene El Molino Formation of the Bolivian Central Andes consists of mixed siliciclastic and carbonate strata alternately interpreted as syn-rift, post-rift thermal sag and foreland basin deposits. These deposits can be divided into two lithostratigraphic sequences. The first sequence consists of a carbonate, carbonate sand and mudrock lower member, a middle member consisting entirely of mudrock and an upper member containing carbonates and mudrocks. The second lithostratigraphic sequence contains a lower member composed of carbonate sands, carbonates and mudrocks, and an upper member consisting of a coarsening upwards sequence of sandstones and mudrocks. Within these lithostratigraphic sequences, five …

Go to article

Modal Predicates And Coequations, Alexander Kurz, Jiří Rosický Jan 2002

Modal Predicates And Coequations, Alexander Kurz, Jiří Rosický

Engineering Faculty Articles and Research

We show how coalgebras can be presented by operations and equations. This is a special case of Linton’s approach to algebras over a general base category X, namely where X is taken as the dual of sets. Since the resulting equations generalise coalgebraic coequations to situations without cofree coalgebras, we call them coequations. We prove a general co-Birkhoff theorem describing covarieties of coalgebras by means of coequations. We argue that the resulting coequational logic generalises modal logic.

Go to article

Electronic Structure And Bonding In Metal Porphyrins, Metal=Fe, Co, Ni, Cu, Zn, M.-S. Liao, Steve Scheiner Jan 2002

Electronic Structure And Bonding In Metal Porphyrins, Metal=Fe, Co, Ni, Cu, Zn, M.-S. Liao, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

A systematic theoretical study of the electronic structure and bonding in metal meso-tetraphenyl porphines MTPP, M=Fe, Co, Ni, Cu, Zn has been carried out using a density functional theory method. The calculations provide a clear elucidation of the ground states for the MTPPs and for a series of [MTPP]x ions (x = 2+, 1+, 1−, 2−, 3−, 4−), which aids in understanding a number of observed electronic properties. The calculation supports the experimental assignment of unligated FeTPP as 3A2g, which arises from the configuration (dxy)2(dz …

Go to article

Electronic Structure And Bonding In Unligated And Ligated Feii Porphyrins, M.-S. Liao, Steve Scheiner Jan 2002

Electronic Structure And Bonding In Unligated And Ligated Feii Porphyrins, M.-S. Liao, Steve Scheiner

Chemistry and Biochemistry Faculty Publications

The electronic structure and bonding in a series of unligated and ligated FeII porphyrins (FeP) are investigated by density functional theory (DFT). All the unligated four-coordinate iron porphyrins have a 3A2g ground state that arises from the (dxy)2(dz2)2(dπ)2 configuration. The calculations confirm experimental results on Fe tetraphenylporphine but do not support the resonance Raman assignment of Fe octaethylporphine as 3Eg, nor the early assignment of Fe octamethyltetrabenzporphine as 5B2g. For the six-coordinate Fe–P( …

Go to article

Dynamics Of A Granular Particle On A Rough Surface With A Staircase Profile, J. J. P. Veerman, F. V. Cunha Jr., G. L. Vasconcelos Jan 2002

Dynamics Of A Granular Particle On A Rough Surface With A Staircase Profile, J. J. P. Veerman, F. V. Cunha Jr., G. L. Vasconcelos

Mathematics and Statistics Faculty Publications and Presentations

A simple model is presented for the motion of a grain down a rough inclined surface with a staircase profile. The model is an extension of an earlier model of ours where we now allow for bouncing, i.e., we consider a non-vanishing normal coefficient of restitution. It is shown that in parameter space there are three regions of interest: (i) a region of smaller inclinations where the orbits are always bounded (and we argue that the particle always stops); (ii) a transition region where halting, periodic and unbounded orbits co-exist; and (iii) a region of large inclinations where no halting …

Go to article

Two-Phase Westward Encroachment Of Basin And Range Extension Into The Northern Sierra Nevada, Benjamin E. Surpless, D. F. Stockli, T. A. Dumitru, E. L. Miller Jan 2002

Two-Phase Westward Encroachment Of Basin And Range Extension Into The Northern Sierra Nevada, Benjamin E. Surpless, D. F. Stockli, T. A. Dumitru, E. L. Miller

Earth and Environmental Geosciences Faculty Research

Structural, geophysical, and thermochronological data from the transition zone between the Sierra Nevada and the Basin and Range province at latitude ~39°N suggest ~100 km westward encroachment of Basin and Range extensional deformation since the middle Miocene. Extension, accommodated primarily by cast dipping normal faults that bound west tilted, range-forming fault blocks, varies in magnitude from150% in the Wassuk and Singatse Ranges to the east. Geological and apatite fission track data from exhumed upper crustal sections in the Wassuk and Singatse Ranges point to rapid footwall cooling related to large magnitude extension starting at ~14-15 Ma. Farther to the west, …

Go to article

Thermochronological Constraints On The Timing And Magnitude Of Miocene And Pliocene Extension In The Central Wassuk Range, Western Nevada, D. F. Stockli, Benjamin E. Surpless, T. A. Dumitru Jan 2002

Thermochronological Constraints On The Timing And Magnitude Of Miocene And Pliocene Extension In The Central Wassuk Range, Western Nevada, D. F. Stockli, Benjamin E. Surpless, T. A. Dumitru

Earth and Environmental Geosciences Faculty Research

Apatite fission track and (U-Th)/He thermochronological data provide new constraints on the timing of faulting and exhumation of the Wassuk Range, western Nevada, where east dipping normal faults have accommodated large-magnitude ENE-WSW oriented extension. Extensional deformation has resulted in the exhumation of structurally coherent fault blocks that expose sections of preextensional mostly granitic upper crust in the Grey Hills and central Wassuk Range. These fault blocks display westward tilts of ∼60° and expose preextensional paleodepths of up to ∼8.5 km, based on the structural reconstruction of tilted preextensional Tertiary andesite flows that unconformably overlie Mesozoic basement rocks. Apatite fission track …

Go to article

Solid Phase Extraction Of Pesticides With Determination By Gas Chromatography, Anwar A. Bhuiyan, Harry O. Brotherton Jan 2002

Solid Phase Extraction Of Pesticides With Determination By Gas Chromatography, Anwar A. Bhuiyan, Harry O. Brotherton

Journal of the Arkansas Academy of Science

A simple, rapid, and effective method for the extraction of fifteen organochlorine and organophosphorus pesticides based on the use of solid phase Bond Elut C-18 cartridges was studied as an alternative method to those based on extraction with organic solvents. Solid phase extraction is an attractive chromatographic sample preparation technology that reduces analysis time, costs, labor, and solvent consumption relative to traditional liquid/liquid extraction methods. The sample recoveries with the use of solid phase extractions were excellent for most pesticides. Analyte concentration by a factor as great as 1000-fold was achieved readily. The adsorbed pesticides were eluted from the solid …

Go to article

Simulation Video Electric Single Particle Aerodynamic Relaxation Time Analyzers, Steve Farmer, Robert A. Sims Jan 2002

Simulation Video Electric Single Particle Aerodynamic Relaxation Time Analyzers, Steve Farmer, Robert A. Sims

Journal of the Arkansas Academy of Science

The simulation of physical parameters provides a virtual environment for the design and optimization of instrumentation. applying physical laws and theorems to natural phenomena defines the behavior of analytical processes. Simulation provides means for the adjustment of specific operating parameters while maintaining the repeatability of constant parameters. The video Electric Single Particle Aerodynamic Relaxation Time Analyzer (VESPART) is an instrument that provides the diameter and charge-to-mass (q/m) ratio of particles. The simulation of the VESPART requires the modeling of the physical environment and application of modeling to simulations. Simulation includes characterization of the various natural forces that "feet particle motion …

Go to article

Alumina And Synthesis Intermediates Derived From Diethylkaluminum Amide, Benzaldehyde And Water, Stephen E. Hall, Lize Wilcox, William S. Tyree, David A. Lindquist, Malay K. Mazumder Jan 2002

Alumina And Synthesis Intermediates Derived From Diethylkaluminum Amide, Benzaldehyde And Water, Stephen E. Hall, Lize Wilcox, William S. Tyree, David A. Lindquist, Malay K. Mazumder

Journal of the Arkansas Academy of Science

The reaction of diethylaluminum amide [Et2AINH2] with benzaldehyde in toluene produces a solution of ethylaluminoxane polymer [EtAlO] and hydrobenzamide [PhCH=NCH(Ph)N=CHPh]. Alumina then is precipitated by the addition of water. Transition aluminas that may be useful in heterogeneous catalyst applications are obtained after calcining. Details of the chemistry of solution intermediates according to 1H NMR and the properties of the alumina product according to surface area analyses and powder x-ray diffraction are described.

Go to article

Bedrock Geology Of West Fork Quadrangle, Washington County, Arkansas, Jack T. King, Maria E. King, Stephen K. Boss Jan 2002

Bedrock Geology Of West Fork Quadrangle, Washington County, Arkansas, Jack T. King, Maria E. King, Stephen K. Boss

Journal of the Arkansas Academy of Science

A digital geologic map of West Fork quadrangle was produced at 1:24,000 scale using the geographic information system (GIS) software Maplnfo. Data regarding stratigraphic relations observed in the field were digitized onto the United States Geological Survey (USGS) digital raster graphic (DRG) of West Fork quadrangle. The geology of West Fork quadrangle consists of sedimentary rocks of the Mississippian and Pennsylvanian systems. The Fayetteville Shale and Pitkin Formation represent the Mississippian system. The Hale, Bloyd, and Atoka Formations represent the Pennsylvanian System. Each of these formations consists of members that were mapped at 1:24,000 scale, and this mapping effort represents …

Go to article

Modification Of Surface Properties Of Polymeric Materials, Rajesh Sharma, Robert A. Sims, Malay K. Mazumder Jan 2002

Modification Of Surface Properties Of Polymeric Materials, Rajesh Sharma, Robert A. Sims, Malay K. Mazumder

Journal of the Arkansas Academy of Science

Polymeric materials are successfully used in virtually all industries ranging from semiconductors, and coatings, to household appliances, automotive, and biomedical implants. Polymers generally have excellent bulk physical and chemical properties. However, certain properties of polymers such as low surface energy, low wettability, and high electrical resistivity sometimes limit their applications. Changing the bulk formulation of the polymers can alter some of these properties, but in general this is not acceptable as it can affect "desirable" bulk properties. Surface modification techniques have been used to alter polymer surfaces without affecting the bulk properties of the material. Most polymers have very high …

Go to article

Revised Bedrock Geology Of War Eagle Quadrangle, Benton County, Arkansas, Robert A. Sullivan, Stephen K. Boss Jan 2002

Revised Bedrock Geology Of War Eagle Quadrangle, Benton County, Arkansas, Robert A. Sullivan, Stephen K. Boss

Journal of the Arkansas Academy of Science

A digital geologic map of War Eagle quadrangle (WEQ) was produced at the 1:24000 scale using the geographic information system (GIS) software ArcView® by digitizing geological contacts onto the United States Geological Survey (USGS) digital raster graphic (DRG). The geology of WEQ consists of sedimentary rocks of Ordovician (Cotter, Powell, and Everton Formations), Devonian (Clifty Formation and Chattanooga Shale), and Mississippian (St. Joe-Boone, Batesville, and Fayetteville Formations) systems. Impoundment of Beaver Lake in 1966 inundated most Ordovician rocks cropping out in WEQ, but all three formations were present in isolated outcrops along the present shoreline of the lake. The St. …

Go to article

Environment-Based Education: Policy, Practice, And Place, Eric N. Wickwire Jan 2002

Environment-Based Education: Policy, Practice, And Place, Eric N. Wickwire

All Master's Theses

The policies of the environment-based education movement are benefiting teachers and students participating in several model programs operating in the United States. Place-centered learning enhances the interdisciplinary practice of Essential Academic Learning Requirements, and actively engages students in local issues. The study of cultural landscapes encourages a sense of place within the Lower Columbia River Gorge, and fosters student connections with the Dalles Mountain Ranch. Policy recommendations are made for environment-based learning in Washington State's public schools. An example place-centered curriculum is outlined for practice at the Dalles Mountain Ranch, and a residential environmental learning center is proposed in the …

Go to article

Laman Web Jawatankuasa Peristilahan Sains Komputer Dan Teknologi Maklumat (Lwjp), Mohd Nor Mohd Lafiz Jan 2002

Laman Web Jawatankuasa Peristilahan Sains Komputer Dan Teknologi Maklumat (Lwjp), Mohd Nor Mohd Lafiz

Student Works (2000-2009)

Laman Web Jawatankuasa Peristilahan Sains Komputer dan Teknologi Maklumat (LWJP). Projek Ilmiah Tahap Akhir II, Fakulti Sains Komputer dan Teknologi Maklumat, Universiti Malaya, Sesi 2001/2002. LWJP adalah laman web dibangunkan khas untuk kegunaan Jawatankuasa Peristilahan Sains Komputer dan Teknologi Maklumat (Jawatankuasa), Fakulti Sains Komputer dan Teknologi Maklumat, Universiti Malaya. Ianya bertujuan untuk menyenangkan dan melicinkan segala aktiviti badan ini. Melalui laman web ini, terdapat satu pautan ke Sistem e-Istilah yang sedia ada yang mana sistem ini merupakan kamus istilah Sains Komputer dan Teknologi Maklumat yang beroperasi atas talian (on-line). LWJP dibangunkan dengan menggunakan Microsoft Visual InterDev, Microsoft FrontPage, Microsoft Access, …

Go to article

Controlling Web Query Execution In A Web Warehouse, Sanjay Kumar Madria, Sourav S. Bhowmick Jan 2002

Controlling Web Query Execution In A Web Warehouse, Sanjay Kumar Madria, Sourav S. Bhowmick

Computer Science Faculty Research & Creative Works

Most of the contemporary Web query systems have limited capabilities in controlling Web query execution. Such query facility is important as it gives us an opportunity to optimize the evaluation of a Web query. We address this issue in the context of our Web warehousing system called WHOWEDA (Warehouse Of Web Data). Specifically, we investigate different types of constraints (related to query execution) which may be imposed on a Web query such as number of query results, time of execution, restrict the evaluation of a query to specified set of Web sites, etc. An important feature of our approach is …

Go to article

Sistem Pengurusan Bengkel Akademia, Wan Abdullah Wan Azlee Jan 2002

Sistem Pengurusan Bengkel Akademia, Wan Abdullah Wan Azlee

Student Works (2000-2009)

Sistem Pengurusan Bengkel Akademia (SPBA) adalah sistem yang akan dibangunkan dengan tujuan dapat menguruskan maklumat-maklumat penting yang perlu disimpan oleh sesebuah organisasi khususnya Fakulti Sains Komputer dan Teknologi Maklumat, Universiti Ma1aya(FSKTM). Ia membolehkan proses pengemaskinian, capaian dan menukar data menjadi lebih mudah serta mempunyai ciri-ciri keselamatan. Ia akan membantu kakitangan akademik dan kakitangan sokongan yang dipertanggungjawab untuk menyelenggara data dan maklumat dengan lebih sistematik dan efektif. Di samping itu ia dapat dijadikan prosedur piawai untuk menguruskan bengkel dan pada masa yang sama sistem ini mampu menggalakkan perkongsian makiumat. Pembangunan SPBA ini adalah untuk menggantikan sistem manual yang sedia ada dalam …

Go to article

Sistem Jadual Waktu Elektronik, Mohd Noh Mohd Nizam Jan 2002

Sistem Jadual Waktu Elektronik, Mohd Noh Mohd Nizam

Student Works (2000-2009)

Projek llmiah Tahap Akhir II (WXES3182) ini merupakan salah satu keperluan kursus yang perlu diambil sebelum seseorang pelajar Ijazah Sarjana Muda Sains Komputer itu bergelar graduan unversiti. Bagi tujuan itu saya telah membuat keputusan membina suatu sistem pentadbiran jadual waktu untuk FakuJti Sains Komputer & Teknologi Maklumat dan sistem ini saya namakan sebagai Sistem Jadual Waktu Elektronik (SJWE). SJWE ini dibangunkan oleh dua orang dan setiap orang membuat domain yang berlainan. Rakan saya Mohd. Sirhan Shabrani Bin Mt. Salleh membuat bahagian pentadbiran jadual waktu (Administration) di mana bahagian ini meliputi kerja-kerja yang perlu mempertimbangkan proses-proses yang perlu dijalankan sebelmn suatu …

Go to article

Quantitative Analysis Of Transmission Power Control In Wireless Ad-Hoc Networks, Seung Jong Park, R. Sivakumar Jan 2002

Quantitative Analysis Of Transmission Power Control In Wireless Ad-Hoc Networks, Seung Jong Park, R. Sivakumar

Computer Science Faculty Research & Creative Works

In this paper, we address the issue of transmission power control in wireless ad-hoc networks. In general, it is assumed that the minimum transmission power required to keep the network connected achieves the optimal throughput performance in an ad-hoc network. In contrast, we show that using the minimal transmission range might not always result in optimal throughput performance. Using both throughput and throughput per unit energy as the optimization criteria, we demonstrate that the optimal transmission power is generically a function of the number of stations, the network size, and the traffic load. In particular, we observe that the optimal …

Go to article

Discrete Predictive Analysis In Probabilistic Safety Assessment, Paul Kvam, J. Glenn Miller Jan 2002

Discrete Predictive Analysis In Probabilistic Safety Assessment, Paul Kvam, J. Glenn Miller

Department of Math & Statistics Faculty Publications

This paper presents methods for predicting future numbers of component failures for probabilistic safety assessments (PSAs). The research is motivated and illustrated by discrete failure data from the nuclear industry, including failure counts for emergency diesel generators, pumps, and motor operated valves. Failure counts are modeled with Poisson and binomial distributions. Multiple-failure environments create extra problems for predictive inference, and are a primary focus of this paper. Common cause failures (CCFs), in particular, refer to the simultaneous failure of system components due to an external event. CCF prediction is investigated, and approximate inference methods are derived for various CCF models.

Go to article

Common Cause Failure Prediction Using Data Mapping, Paul H. Kvam, J. Glenn Miller Jan 2002

Common Cause Failure Prediction Using Data Mapping, Paul H. Kvam, J. Glenn Miller

Department of Math & Statistics Faculty Publications

To estimate power plant reliability, a probabilistic safety assessment might combine failure data from various sites. Because dependent failures are a critical concern in the nuclear industry, combining failure data from component groups of different sizes is a challenging problem. One procedure, called data mapping, translates failure data across component group sizes. This includes common cause failures, which are simultaneous failure events of two or more components in a group. In this paper, we present methods for predicting future plant reliability using mapped common cause failure data. The prediction technique is motivated by discrete failure data from emergency diesel generators …

Go to article

Levy-Like Continuity Theorems For Convergence In Distribution, Theodore P. Hill, Ulrich Krengel Jan 2002

Levy-Like Continuity Theorems For Convergence In Distribution, Theodore P. Hill, Ulrich Krengel

Research Scholars in Residence

Levy’s classical continuity theorem states that if the pointwise limit of a sequence of characteristic functions exists, then the limit function itself is a characteristic function if and only if the limit function satisfies a single universal limit condition (in his case, the limit at zero is one), in which case the underlying measures converge weakly to the probability measure represented by the limit function. It is the purpose of this article to give a number of direct analogs of L´evy’s theorem for other probability-representing functions including moment sequences, maximal moment sequences, mean-residual-life functions, Hardy-Littlewood maximal functions, and failure-rate functions. …

Go to article

Random Probability Measures With Given Mean And Variance Running Title: Random Probability Measures, Lisa Bloomer, Theodore P. Hill Jan 2002

Random Probability Measures With Given Mean And Variance Running Title: Random Probability Measures, Lisa Bloomer, Theodore P. Hill

Research Scholars in Residence

This article describes several natural methods of constructing random probability measures with prescribed mean and variance, and focuses mainly on a technique which constructs a sequence of simple (purely discrete, finite number of atoms) distributions with the prescribed mean and with variances which increase to the desired variance. Basic properties of the construction are established, including conditions guaranteeing full support of the generated measures, and conditions guaranteeing that the final measure is discrete. Finally, applications of the construction method to optimization problems such as Plackett’s Problem are mentioned, and to experimental determination of average-optimal solutions of certain control problems.

Go to article

Self-Assembly Of Spatially Separated Silicon Structures By Si Heteroepitaxy On Ni Disilicide, Elena A. Guliants, Chunhai Ji, Wayne A. Anderson Jan 2002

Self-Assembly Of Spatially Separated Silicon Structures By Si Heteroepitaxy On Ni Disilicide, Elena A. Guliants, Chunhai Ji, Wayne A. Anderson

Electrical and Computer Engineering Faculty Publications

A nonlithographic approach to produce self-assembled spatially separated Si structures for nanoelectronic applications was developed, employing the metal-induced silicon growth. Densely packed Si whiskers, 500–800 nm thick and up to 2500 nm long, were obtained by magnetron sputtering of Si on a 25 nm thick Ni prelayer at 575 °C. The nucleation of the NiSi2 compound at the Ni–Si interface followed by the Si heteroepitaxy on the lattice-matched NiSi2 is suggested to be the driving force for the whisker formation.

Go to article

Magnetic Measurements On Ga1-Xmnxs In High Fields Using The Cantilever Technique, Carl W. Maymi Jan 2002

Magnetic Measurements On Ga1-Xmnxs In High Fields Using The Cantilever Technique, Carl W. Maymi

All Volumes (2001-2008)

High field magnetic measurements have been taken on the III-VI Diluted Magnetic Semiconductor Ga1-xMnxS at the National High Magnetic Field Laboratory. This paper discusses the calibration of magnetic measurements made using the cantilever technique. It has been discovered that efficiency of cantilevers may decline over time, signaled by the onset of an oscillatory effect in the cantilever data.

Go to article

Development Of The Continuously Variable Volume Reactor For Flow Injection Analysisdesign, Capabilities And Testing, Linda L. Lipe, Suzanne M. Purinton, Elizabeth Mederios, C Chad Harrell, Cynthia Efta, Melissa Murray, Meredith Wood, Ray-Bernard Portier, Stuart J. Chalk Jan 2002

Development Of The Continuously Variable Volume Reactor For Flow Injection Analysisdesign, Capabilities And Testing, Linda L. Lipe, Suzanne M. Purinton, Elizabeth Mederios, C Chad Harrell, Cynthia Efta, Melissa Murray, Meredith Wood, Ray-Bernard Portier, Stuart J. Chalk

All Volumes (2001-2008)

A new apparatus for mixing sample and reagent in flow injection analysis is described. The continuously variable volume reactor (CVVR) replaces the conventional mixing coil in a flow injection manifold to provide mixing and dilution. A linear actuator motor allows control of the chamber volume via Lab VIEW software. The chamber volume can be incremented in steps of 1 uL over the range 68-1704 uL. In addition, the chamber has an integral variable-speed stirring unit that is also under computer control. Experiments were performed to evaluate the dispersion characteristics of this new device, evaluate the volume reproducibility, and understand the …

Go to article

First Prev Next Last